AFP/GettyImages(CAIRO) -- Following a night of deadly clashes, which led to six deaths and hundreds of injuries in Cairo Wednesday, tens of thousands of Egyptians continue to protest outside the presidential palace, demanding the ouster of President Mohammed Morsi. Protesters began calling for Morsi's removal after his refusal to give up absolute power in order to write a new constitution.

Those very same people filled these same streets two years ago. Today they're chanting the same exact songs, only replacing Hosni Mubarak's name with Mohammad Morsi.

"He has become, like -- you think you didn't like Mubarak? This is worse than Mubarak," said Nadia Kamal, an activist and filmmaker in Egypt.

The president's defiance has only increased the tension, and now his opponents vow to fight on in the name of democracy. They fear the new constitution will not protect many of the freedoms for which they fought so hard.

In a speech Morsi delivered Thursday, he gave no indication he might make meaningful concessions, but he did invite the opposition to the palace for talks Saturday.

President Obama called Morsi Thursday, expressing his deep concern about the mounting deaths and injuries of protesters in Egypt. He emphasized that Egyptian lawmakers should make clear to their supporters that violence will not be tolerated.

While President Obama welcomed Morsi's call for a dialogue with his opposition, he stressed this dialogue should take place without preconditions.

He also repeated the United States' continued support for the Egyptian people and their transition to a democracy that respects the rights of all Egyptians.